1. Field of the Invention.
The invention relates to fruit presses which operate to dejuice, dewater or deoil fruits and other liquid-containing materials, such as grapes, apples, pears, crabapples, sugar beets, berries, cherries, olives, pineapples, hops and other herbs, spent grain, sludges, such as sewage sludges, and seeds, such as olive oil seeds, sesame seeds, peanuts, linseeds and the like.
2. State of the Art.
Numerous machines have been designed and utilized for the purpose of dejuicing, dewatering and deoiling fruits and other materials, and most usually for dejuicing such fruits as apples, grapes and pears, for example. A number of different types of presses have been developed for this purpose, and a typical such device of current usage includes a plurality of horizontally extending, vertically moveable platens, operated by suitable hydraulic systems which compress the fruit against a table, the fruit being contained in a specially designed press cloth.
Our U.S. Pat. No. 4,033,253, issued July 5, 1977, is directed to an improvement on the foregoing state-of-the-art apparatus and processes, using a rigid-sided conveyor means to contain the fruit mash. However, the state-of-the-art devices and the apparatus of our U.S. Pat. No. 4,033,253 have several substantial limitations, among which are the expense of plural platens and control systems therefor and of the conveyor system and related equipment. The apparatus of our U.S. Pat. No. 4,033,253 also requires the additional expense, and potential for mechanical difficulties, of the moving sides and the control means therefor.
The use of press apparatus including at least one horizontally moveable compressing device is known in the art, and U.S. Pat. No. 3,070,003 shows such a press utilizing and compressing cylinder 12 and indexing back-up closer 18, which acts as a barrier against which the material is compressed remains fixed while the enclosure 15 indexes rearwardly, as seen in FIG. 4, to discharge cake 3. Other relevant patents known to applicant are U.S. Pat. Nos. 115,731, 165,076, 215,606, 250,979, 1,345,963, 1,922,513, 2,738,550, 3,055,289, 3,082,682, 3,550,775, 3,673,952 and 3,828,663. References cited in the parent case are U.S. Pat. Nos. 701,882, 1,071,020, 1,135,309 and 2,055,697 and British Pat. No. 1,397,133 were cited in the parent application Ser. No. 789,729.
The devices of the prior art have not proven satisfactory to provide a relatively high-speed, relatively low cost, high efficiency, compact device for deliquifying fruits and other materials.
Another shortcoming of the devices of the prior art is the tendency of the spaces in the screens or platen faces, through which the juice is expressed, to become clogged. These prior art apparatus make no useful provision for unclogging the apertures. Clogging of apertures reduces the rate of drainage of liquid from the press cage and may reduce the amount of recovered liquid, increase the press cycle time period and detract from the optimum efficiency of the press cycle.